* {
    margin: 10;
    padding: 0;
}

ul,
ol,
li {
    list-style: none;
}

.box {
    width: 600px;
    height: 400px;
    border: 10px solid blue;
    margin: 30px auto;
    display: flex;
    flex-direction: column;
}

ul {
    width: 100%;
    height: 50px;
    display: flex;
    justify-content: center;
    align-items: center;
}

ul {
    > li {
        flex: 1;
        height: 100%;
        display: flex;
        justify-content: center;
        align-items: center;
        color: #fff;
        background-color: red;
        font-size: 30px;

        &.active {
            background-color: yellow;
        }

        img {
            width: 100px;
        }
    }
}

ol {
    flex: 1;
    position: relative;
    width: 100%;
}

ol {
    > li {
        width: 100%;
        height: 100%;
        position: absolute;
        top: 0;
        left: 0;
        background-color: #ccc;
        color: #fff;
        font-size: 100px;
    
        display: none;
        justify-content: center;
        align-items: center;

        &.active {
            display: flex;
        }
    }
}